Complex fractures of the proximal humerus: role of CT in treatment

Incidence of secondary displacement after osteosynthesis of proximal humerus fractures: a retrospective study of 185 cases

Proximal humerus fractures are the third most common fracture in patients over 65 years of age. There is no clear consensus regarding their treatment. The objective of this retrospective observational study was to calculate the incidence of secondary displacement after osteosynthesis of these fractures and to identify possible risk factors. 185 cases were reviewed and all osteosynthesized fractures between January 2008 and December 2016 were included. Data collected included age, sex, body mass index, alcohol and tobacco use, bone mineral density of the proximal humerus, fracture type, initial displacement, management time, type of treatment, surgeon's experience and expertise, and postoperative reduction quality. A radiographic follow-up was done at least 3 months following the fracture (until consolidation). The definition of secondary displacement was: varus/valgus displacement >10°, tuberosity translation >5 mm, articular effraction or material breakage. 53 secondary displacements were found, with an incidence of 28.6%. Seventy-two percent were diagnosed at the first follow-up visit, which occurred at an average of 29 days postoperatively. Among all factors studied, only two were statistically significant for secondary displacement: 1) low proximal humeral bone density (defined by a Tingart index <4) appears to be a risk factor, with a calculated relative risk of 2.71 (p = 0.04); and 2) the operator's specialization in the upper limb appears to be a protective factor, with a relative risk of 0.27 (p = 0.01). A similar high incidence of complications after osteosynthesis of the proximal humerus is found in the literature, confirming the difficulty in managing these fractures. More attention should be given to patients with low bone density.

Proximal Humerus Fractures in the Pediatric Population

PURPOSE OF REVIEW

The purpose of this review is to review recent literature focusing on proximal humerus anatomy, epidemiology of these fractures, diagnosis and treatment options, and clinical outcomes.

RECENT FINDINGS

Non- or minimally displaced proximal humerus fractures treated nonoperatively do not lead to short- or long-term complication and do not cross over to operative treatment. There is a higher rate of operative management with older age, increased injury severity score, treatment at an adult hospital, and private insurance. Operative management is preferred with closed or open reduction and percutaneous pinning, but elastic nailing and plate fixation are other options with good postoperative outcomes. Pediatric proximal humerus fractures occur after fall onto the affected shoulder or arm. Diagnosis is usually made with radiographs. Understanding the proximal humerus anatomy is critical to the proper management of these injuries to aid reduction and predict remodeling potential. There is considerable debate around the management of proximal humerus fractures in the pediatric population. Treatment is based on patient age, fracture displacement, and remodeling capacity. Nonoperative management is successful in younger patients or less displaced fractures, and operative management is usually considered in older patients with more displaced fractures.

Diagnostic accuracy of intraoperative CT-imaging in complex articular fractures - a cadaveric study

Anatomic reconstruction of articular fractures is one of the critical factors in later achieving good functional outcome. Intraoperative 3D imaging has been shown to offer better evaluation and therefore can significantly improve the results. The purpose of this study was to assess the difference between intraoperative three-dimensional fluoroscopy (3D) and intraoperative computed tomography (iCT) imaging regarding fracture reduction, implant placement and articular impressions in a distal humeral fracture model. AO type 13-B2 fracture pattern were created in upper extremity cadaver specimens. Articular step-offs, intra-articular screw placement and intraarticular impressions of different degrees of severity were created. All specimens had imaging performed. For each articular pattern 3D fluoroscopy in standard (3Ds) and high quality (3Dh) were performed (Arcadis Orbic, Siemens, Germany) as well as an intraoperative CT scan (iCT, Airo, Brainlab, Germany). Three observers evaluated all imaging studies regarding subjective and objective parameters. iCT is more precise than 3D fluoroscopic imaging for detection of articular impressions. Articular step-offs and intraarticular screw placement are similar for iCT and 3D. Subjective imaging quality is the highest for iCT and lowest for 3Ds. Intraoperative CT may be particularly useful in assessing articular impressions and providing a good subjective image quality for the surgeon.

Size of greater tuberosity fragment: a risk of iatrogenic injury during shoulder dislocation reduction

PURPOSE

Shoulder dislocation with greater tuberosity fractures (GTF) is becoming increasingly common, as is the number of cases of iatrogenic humeral neck fractures (IHNF) during reduction. This study investigated the relationship between size of greater tuberosity fragment and occurrence of IHNF in patients with shoulder dislocation and GTF.

METHODS

A retrospective study was made to identify all patients presenting with shoulder dislocation with GTF between September 2014 and July 2016. There were 74 patients with an average age of 52.4 years (range 18-84 years) representing 76 cases of shoulder dislocation associated with GTF. Patient age, injury mechanism and location, treatment waiting time, and reduction method were noted. Using conventional anterior-posterior view radiographs, three points were identified as A, B, and C. Distance ratios between AC and AB were calculated, then the resulting ratio was compared to a critical value of 0.4.

RESULTS

More iatrogenic fractures occurred in cases where the AC/AB ratio exceeded 0.4. Most (13) occurred during emergency Hippocratic manual reduction. Only five of 18 iatrogenic fractures (27.78%) occurred during surgery while under traction. Women ran a higher risk of iatrogenic fracture than men (female/male ratio 8:1). On average, women were older than men at the time of fracture (59.75 years for women vs. 42 years for men).

CONCLUSIONS

A statistically significant relationship exists between size of greater tuberosity fragment and occurrence of iatrogenic humeral neck fractures during the reduction of shoulder dislocation. The larger the greater tuberosity fragment, the higher the incidence of iatrogenic humeral neck fractures. For such fracture dislocations, we recommend open reduction with internal fixation directly and using a Kirschner wire in advance to reinforce the proximal humerus before reduction of the shoulder.

Isolated greater tuberosity fractures of the proximal humerus: anatomy, injury patterns, multimodality imaging, and approach to management

The greater tuberosity is an important anatomic structure and its integrity is important for shoulder abduction and external rotation. Isolated fractures of the greater tuberosity are often subtle and may not be detected on initial radiographs. Clinically, these patients display symptoms which mimic a full thickness rotator cuff tear. It is important to differentiate these two entities, as their treatment is different (typically nonsurgical management for minimally displaced fractures versus rotator cuff repair for acute full thickness rotator cuff tears). When greater tuberosity fractures are significantly displaced and allowed to heal without anatomic reduction, they can lead to impingement. This article will review greater tuberosity anatomy and function, as well as the clinical presentation and multimodality imaging findings of greater tuberosity fractures. Imaging optimization, pitfalls, and clinical management of these fractures will also be discussed.

Misses and errors in upper extremity trauma radiographs

OBJECTIVE

The article reviews a select group of traumatic upper extremity injuries that can be easily misinterpreted on radiographs.

CONCLUSION

The awareness of these specific injuries and an understanding of their underlying pathophysiology and the role that radiographs can play in their evaluation will give the reader the best opportunity to make the important imaging findings and guide appropriate treatment.

Accurate Measurement of Greater Tuberosity Displacement Without Computed Tomography: Validation of a Method on Plain Radiography to Guide Surgical Treatment

INTRODUCTION

Residual displacement of greater tuberosity (GT) fractures has been shown to negatively affect shoulder function. However, accurate measurement of GT displacement remains a problem with errors up to 13 mm on plain radiography (XR). A new GT ratio for measuring fracture displacement on XR is described, validated, and correlated with computed tomography (CT) and surgical decision making.

METHODS

A retrospective review of shoulder radiographs was performed from 2007 to 2010 to identify all cases of isolated GT fractures with both XR and CT. The GT ratio was performed on all XR and correlated with superior GT displacement measured on CT. The GT ratio was then tested for accuracy of surgical decision using 5-mm superior displacement on CT as the cutoff. Finally, the inter- and intraobserver reliabilities of the GT ratio were calculated and compared with the Neer and Arbeitsgemeinschaft fur Osteosynthesefragen (AO) classifications.

RESULTS

Forty cases of acute GT fractures with XR and CT were identified. The GT ratio correlated very well with superior displacement on CT (Pearson correlation = 0.852, P < 0.01) and accurately classified GT fractures as "surgical" (n = 9, 23%) or "nonsurgical" (n = 31, 77%). GT ratios ≤0.00 were nonsurgical, ≥0.50 were surgical, and 0.00-0.50 warranted further imaging (P < 0.01). The GT ratio performed as well as or better than the AO and Neer classifications for inter- and intraobserver reliabilities.

CONCLUSIONS

The GT ratio described in this study correlates very well with CT for superior GT fracture displacement. It involves significantly less radiation and accurately classifies GT fractures as nonsurgical (ratio < 0.00), surgical (ratio > 0.50), or as benefiting from further imaging (0.00-0.50). It performs as well or better than the Neer or AO classification.

LEVEL OF EVIDENCE

Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Diagnostic accuracy of two-dimensional and three-dimensional imaging and modeling of radial head fractures

To tests the hypothesis that classification and characterization of fractures of the radial head is more accurate with 3D than 2D computed tomography images and radiographs, using a prospective study design with intraoperative inspection as the reference standard. Treating surgeons and first assistants completed a questionnaire assigning a fracture type according to the Broberg and Morrey modification of Mason's classification, evaluating selected fracture characteristics, and electing preferred management based upon radiographs and 2D images alone; then adding 3D-CT; then 3D printed physical models; and finally intra-operative visualization. The addition of the 3D CT and physical models improved the sensitivity for fracture line separating the entire head from the neck, comminution of the radial neck, fracture involving the articular surface, articular fracture gap greater than 2 mm, impacted fracture fragments, greater than 3 articular fragments, and articular fragments judged too small to repair. There were no significant differences in diagnostic performance with the addition of 3D models. The addition of 3D CT and models improved the reliability of Broberg and Morrey classification. We conclude that 3DCT and 3D physical modeling provide more accurate fracture classification and characterization of fracture of the radial head with less proposed variability in treatment. We did not demonstrate a clear advantage for modeling over 3DCT reconstructions.

LEVEL OF EVIDENCE

Diagnostic, Level I.

Minimally displaced fractures of the greater tuberosity: outcome of non-operative treatment

BACKGROUND

Minimally displaced (<3 mm) and non-displaced fractures of the proximal humerus are a common source of disability; nevertheless, there is no agreement on the recommended rehabilitation program in these patients. The purpose of this study was to evaluate the outcome of this group of patients and describe the rehabilitation protocol we have used for the treatment of this injury.

METHODS

We retrospectively analyzed the records of patients diagnosed with minimally displaced (<3 mm) fractures of the greater tuberosity who were admitted to our institute between June 2007 and May 2008. Patients were treated with a three-phase protocol. In the first phase, patients were immobilized in a sling for 3 weeks. In the second phase, pendular and active assisted exercises were begun 3 to 6 weeks after the injury. In the third phase, active exercises were commenced starting 6 weeks after injury.

RESULTS

Sixty-nine patients matched our inclusion and exclusion criteria. At an average follow-up of 31 months (range, 26-41 months), the average Constant score improved from 40 points (range, 33-58 points) to 95 points (range, 75-100 points). Average satisfaction score improved from 4.2 of 10 (range, 2-6) to 9.5 of 10 (range, 7-10). The reported average duration of pain and decreased range of motion from the time of injury was 8.1 months (range, 1-24 months).

CONCLUSIONS

When the diagnosis of a minimally displaced fracture of the proximal humerus is made, the patient can be reassured that a favorable outcome is anticipated with a staged rehabilitation protocol. Nevertheless, clinicians and patients should be aware that full recovery from the injury may take an average of 8 months.

Interobserver reliability of classification and characterization of proximal humeral fractures: a comparison of two and three-dimensional CT

BACKGROUND

Interobserver reliability for the classification of proximal humeral fractures is limited. The aim of this study was to test the null hypothesis that interobserver reliability of the AO classification of proximal humeral fractures, the preferred treatment, and fracture characteristics is the same for two-dimensional (2-D) and three-dimensional (3-D) computed tomography (CT).

METHODS

Members of the Science of Variation Group--fully trained practicing orthopaedic and trauma surgeons from around the world--were randomized to evaluate radiographs and either 2-D CT or 3-D CT images of fifteen proximal humeral fractures via a web-based survey and respond to the following four questions: (1) Is the greater tuberosity displaced? (2) Is the humeral head split? (3) Is the arterial supply compromised? (4) Is the glenohumeral joint dislocated? They also classified the fracture according to the AO system and indicated their preferred treatment of the fracture (operative or nonoperative). Agreement among observers was assessed with use of the multirater kappa (κ) measure.

RESULTS

Interobserver reliability of the AO classification, fracture characteristics, and preferred treatment generally ranged from "slight" to "fair." A few small but statistically significant differences were found. Observers randomized to the 2-D CT group had slightly but significantly better agreement on displacement of the greater tuberosity (κ = 0.35 compared with 0.30, p < 0.001) and on the AO classification (κ = 0.18 compared with 0.17, p = 0.018). A subgroup analysis of the AO classification results revealed that shoulder and elbow surgeons, orthopaedic trauma surgeons, and surgeons in the United States had slightly greater reliability on 2-D CT, whereas surgeons in practice for ten years or less and surgeons from other subspecialties had slightly greater reliability on 3-D CT.

CONCLUSIONS

Proximal humeral fracture classifications may be helpful conceptually, but they have poor interobserver reliability even when 3-D rather than 2-D CT is utilized. This may contribute to the similarly poor interobserver reliability that was observed for selection of the treatment for proximal humeral fractures. The lack of a reliable classification confounds efforts to compare the outcomes of treatment methods among different clinical trials and reports.

Diagnostic accuracy of 2- and 3-dimensional imaging and modeling of distal humerus fractures

PURPOSE

This investigation used prospectively recorded intraoperative evaluation as the reference standard for distal humerus fracture type and characteristics, in order to measure the diagnostic performance characteristics of computed tomography (CT) and physical models. In secondary analyses, we assessed the reliability of classification.

METHODS

Thirty-five fractures were evaluated by the treating surgeon and first assistant on radiographs and 2-dimensional CT (2DCT) images first; a second time based on radiographs and 2- and 3-dimensional CT (3DCT) images; a third time based on 2- and 3DCT as well as 3D physical models; and a fourth time based on intraoperative visualization of the fracture characteristics. The intraoperative evaluation of the attending surgeon was used as the reference standard.

RESULTS

The addition of 3DCT and the 3D models to 2DCT and radiographs led to significant improvements in sensitivity, but not specificity, in the diagnosis and proposed treatment, and improved the interobserver agreement with respect to specific fracture characteristics but not classification.

CONCLUSION

Increasingly sophisticated imaging and modeling leads to slight but significant improvements in diagnostic performance characteristics and interobserver agreement on fracture characteristics.

Classification and treatment of proximal humerus fractures: inter-observer reliability and agreement across imaging modalities and experience

SUMMARY

Proximal humerus fractures (PHF) are common injuries, but previous studies have documented poor inter-observer reliability in fracture classification. This disparity has been attributed to multiple variables including poor imaging studies and inadequate surgeon experience. The purpose of this study is to evaluate whether inter-observer agreement can be improved with the application of multiple imaging modalities including X-ray, CT, and 3D CT reconstructions, stratified by physician experience, for both classification and treatment of PHFs.

METHODS

Inter-observer agreement was measured for classification and treatment of PHFs. A total of sixteen fractures were imaged by plain X-ray (scapular AP and lateral), CT scan, and 3D CT reconstruction, yielding 48 randomized image sets. The observers consisted of 16 orthopaedic surgeons (4 upper extremity specialists, 4 general orthopedists, 4 senior residents, 4 junior residents), who were asked to classify each image set using the Neer system, and recommend treatment from four pre-selected choices. The results were evaluated by kappa reliability coefficients for inter-observer agreement between all imaging modalities and sub-divided by: fracture type and observer experience.

RESULTS

All kappa values ranged from "slight" to "moderate" (k = .03 to .57) agreement. For overall classification and treatment, no advanced imaging modality had significantly higher scores than X-ray. However, when sub-divided by experience, 3D reconstruction and CT scan both had significantly higher agreement on classification than X-ray, among upper extremity specialists. Agreement on treatment among upper extremity specialists was best with CT scan. No other experience sub-division had significantly different kappa scores. When sub-divided by fracture type, CT scan and 3D reconstruction had higher scores than X-ray for classification only in 4-part fractures. Agreement on treatment of 4 part fractures was best with CT scan. No other fracture type sub-division had significantly different kappa scores.

CONCLUSIONS

Although 3D reconstruction showed a slight improvement in the inter-observer agreement for fracture classification among specialized upper extremity surgeons compared to all imaging modalities, fracture types, and surgeon experience; overall all imaging modalities continue to yield low inter-observer agreement for both classification and treatment regardless of physician experience.

Classification and treatment of proximal humerus fractures: inter-observer reliability and agreement across imaging modalities and experience

SUMMARY

Proximal humerus fractures (PHF) are common injuries, but previous studies have documented poor inter-observer reliability in fracture classification. This disparity has been attributed to multiple variables including poor imaging studies and inadequate surgeon experience. The purpose of this study is to evaluate whether inter-observer agreement can be improved with the application of multiple imaging modalities including X-ray, CT, and 3D CT reconstructions, stratified by physician experience, for both classification and treatment of PHFs.

METHODS

Inter-observer agreement was measured for classification and treatment of PHFs. A total of sixteen fractures were imaged by plain X-ray (scapular AP and lateral), CT scan, and 3D CT reconstruction, yielding 48 randomized image sets. The observers consisted of 16 orthopaedic surgeons (4 upper extremity specialists, 4 general orthopedists, 4 senior residents, 4 junior residents), who were asked to classify each image set using the Neer system, and recommend treatment from four pre-selected choices. The results were evaluated by kappa reliability coefficients for inter-observer agreement between all imaging modalities and sub-divided by: fracture type and observer experience.

RESULTS

All kappa values ranged from "slight" to "moderate" (k = .03 to .57) agreement. For overall classification and treatment, no advanced imaging modality had significantly higher scores than X-ray. However, when sub-divided by experience, 3D reconstruction and CT scan both had significantly higher agreement on classification than X-ray, among upper extremity specialists. Agreement on treatment among upper extremity specialists was best with CT scan. No other experience sub-division had significantly different kappa scores. When sub-divided by fracture type, CT scan and 3D reconstruction had higher scores than X-ray for classification only in 4-part fractures. Agreement on treatment of 4 part fractures was best with CT scan. No other fracture type sub-division had significantly different kappa scores.

CONCLUSIONS

Although 3D reconstruction showed a slight improvement in the inter-observer agreement for fracture classification among specialized upper extremity surgeons compared to all imaging modalities, fracture types, and surgeon experience; overall all imaging modalities continue to yield low inter-observer agreement for both classification and treatment regardless of physician experience.

Indications for computed tomography (CT-) diagnostics in proximal humeral fractures: a comparative study of plain radiography and computed tomography

BACKGROUND

Precise indications for computed tomography (CT) in proximal humeral fractures are not established. The purpose of this study was a comparison of conventional radiographic views with different CT reconstructions with 2 D and 3 D imaging to establish indications for additional CT diagnostics depending on the fractured parts.

METHODS

In a prospective diagnostic study in two level 1 trauma centers, 44 patients with proximal humeral fractures were diagnosed with conventional X-rays (22 AP + axillary views, 22 AP + scapular Y-views) and CT (multi-planar reconstruction (MPR) and maximum intensity projection (MIP)) with 2 D and 3 D imaging. 3 observers assessed the technical image quality, the assessment of the relevant anatomical structures (2-sample-t-test) and the percentage of the osseous overlap of the proximal humerus (Welch-test) using a scoring system. The quality of the different diagnostic methods was assessed according to the number of fractured parts (Bonferroni-Holm adjustment).

RESULTS

There was significantly more overlap of the fractured region on the scapular Y-views (mean 71.5%, range 45-90%) than on axillary views (mean 56.2%, range 10.5-100%). CT-diagnostics allowed a significantly better assessment of the relevant structures than conventional diagnostics (p < 0.05) independently of the fracture severity (two-, three-, and four-part fractures).

CONCLUSION

Conventional X-rays with AP view and a high-quality axillary view are useful for primary diagnostics of the fracture and often but not always show a clear presentation of the relevant bony structures such as both tuberosities, the glenoid and humeral head. CT with thin slices technology and additional 3 D imaging provides always a clear presentation of the fractured region. Clinically, a CT should be performed--independently of the number of fractured parts--when the proximal humerus and the shoulder joint are not presented with sufficient X-ray-quality to establish a treatment plan.

Classification and imaging of proximal humerus fractures

The decision to operate and the selection of the appropriate surgical modality for proximal humerus fractures are largely based on the fracture pattern. Understanding the particular fracture pattern in each case is complicated. Most well-accepted classification systems were developed based on radiographs complemented by intraoperative findings. Three-dimensional reconstructions based on CT currently available in most institutions allow a much better understanding of complex fractures. Modern thinking about fracture classification probably should be revisited in the light of improved imaging techniques.

Fractures of the greater tuberosity of the humerus

Isolated fractures of the greater tuberosity of the humerus can occur in anterior shoulder dislocations or as the result of an impaction injury against the acromion or superior glenoid. Greater tuberosity fractures may be associated with partial-thickness rotator cuff tears and labral tears, which may be the cause of persistent pain after fracture healing. Nondisplaced and minimally displaced fractures are typically treated successfully nonsurgically. Surgical fixation is recommended for fractures with >5 mm of displacement in the general population or >3 mm of displacement in active patients involved in frequent overhead activity. Open surgical repair is performed with suture or screw fixation. Recently, arthroscopic techniques have produced promising results. Careful follow-up and supervised rehabilitation optimize results after both nonsurgical and surgical treatment.

Two and three-dimensional computed tomography for the classification and management of distal humeral fractures. Evaluation of reliability and diagnostic accuracy

BACKGROUND

Complex fractures of the distal part of the humerus can be difficult to characterize on plain radiographs and two-dimensional computed tomography scans. We tested the hypothesis that three-dimensional reconstructions of computed tomography scans improve the reliability and accuracy of fracture characterization, classification, and treatment decisions.

METHODS

Five independent observers evaluated thirty consecutive intra-articular fractures of the distal part of the humerus for the presence of five fracture characteristics: a fracture line in the coronal plane; articular comminution; metaphyseal comminution; the presence of separate, entirely articular fragments; and impaction of the articular surface. Fractures were also classified according to the AO/ASIF Comprehensive Classification of Fractures and the classification system of Mehne and Matta. Two rounds of evaluation were performed and then compared. Initially, a combination of plain radiographs and two-dimensional computed tomography scans (2D) were evaluated, and then, two weeks later, a combination of radiographs, two-dimensional computed tomography scans, and three-dimensional reconstructions of computed tomography scans (3D) were assessed.

RESULTS

Three-dimensional computed tomography improved both the intraobserver and the interobserver reliability of the AO classification system and the Mehne and Matta classification system. Three-dimensional computed tomography reconstructions also improved the intraobserver agreement for all fracture characteristics, from moderate (average kappa [kappa2D] = 0.554) to substantial agreement (kappa3D = 0.793). The addition of three-dimensional images had limited influence on the interobserver reliability and diagnostic characteristics (sensitivity, specificity, and accuracy) for the recognition of specific fracture characteristics. Three-dimensional computed tomography images improved intraobserver agreement (kappa2D = 0.62 compared with kappa3D = 0.75) but not interobserver agreement (kappa2D = 0.24 compared with kappa3D = 0.28) for treatment decisions.

CONCLUSIONS

Three-dimensional reconstructions improve the reliability, but not the accuracy, of fracture classification and characterization. The influence of three-dimensional computed tomography was much more notable for intraobserver comparisons than for interobserver comparisons, suggesting that different observers see different things in the scans-most likely a reflection of the training, knowledge, and experience of the observer with regard to these relatively uncommon and complex injuries.

Proposed protocol for reading images of humeral head fractures

Fractures of the proximal humerus can be treated effectively but require proper characterization. None of the existing classifications intended to facilitate characterization have been satisfactory. We studied proximal humerus fractures using radiographs alone and radiographs plus computed tomography scans to ascertain which imaging studies were most useful to characterize these fractures. We designed an assessment protocol consisting of 17 parameters divided in four groups: cephalodiaphyseal relationship (six parameters), cephalotuberosity relationship (six parameters), humeral head (two parameters), and fracture fragment description (three parameters). The computed tomography scans were assessed using 11 parameters (the same parameters used for assessing radiographs except for the six cephalodiaphyseal parameters). Four observers analyzed the parameters in 30 selected fractures with biplanar radiographic projections (30 patients) and computed tomography scans (22 patients) on two occasions. We found good interobserver reliability and intraobserver reliability with radiographs alone for the cephalodiaphyseal parameters. The best interobserver reliabilities with radiographs plus computed tomography scans were with the number of fragments, displacement of the lesser tuberosity, and extraarticular or articular fractures. Computed tomography allows better assessment of some parameters in characterizing proximal humeral fractures. The use of a structured protocol in reading images seems useful and allows better reliability than reported for other approaches.

LEVEL OF EVIDENCE

Diagnostic study, Level III (study of nonconsecutive patients without consistently applied reference "gold" standard). See the Guidelines for Authors for a complete description of levels of evidence.

Double line sign: a helpful sonographic sign to detect occult fractures of the proximal humerus

The aim of this study was to describe a new sonographic sign of bone fracture and to determine if it can be helpful in decreasing the number of missed fractures of the proximal humerus. Ultrasound (US) of the shoulder was performed in 57 consecutive patients with shoulder pain and/or disability following trauma. All cases were prospectively reviewed for the presence of a humeral fracture. Sonographic signs of fractures, with special emphasis on what was termed the 'double line sign' (DLS), were assessed. Plain radiography was considered the standard of reference and in equivocal cases magnetic resonance imaging (MRI). Twenty-eight patients had a tuberosity complex fracture, which were all detected at US examination. Sonographic features of a fracture were periosteal elevation, corticol bone discontinuity, step-off deformity or a combination of these findings. This study showed that in 26 (93%) patients an additional sonographic feature, a DLS, could be demonstrated. The DLS is a helpful and probably reliable sonographic sign to indicate a humeral fracture. High-spatial-resolution US substantially increases the detection of fractures of the proximal humerus and should be considered as an alternative diagnostic tool prior to computed tomography (CT), MRI and arthroscopy in patients with persisting shoulder pain and/or disability following trauma.

Multidetector computed tomography in acute joint fractures

Conventional radiography plays an essential diagnostic role in the primary evaluation of acute joint trauma. In complex fractures, however, computed tomography (CT) is an imaging modality often used second to radiography. As a result of technical breakthroughs in the field, multidetector CT (MDCT) allows faster imaging and better temporal, spatial, and contrast resolution compared with conventional single-slice spiral CT. MDCT with multiplanar reformation is helpful in disclosing fracture patterns, particularly in complex joint fractures, where they reveal occult fractures and show the exact number of fracture components and their degree of displacement.

Multidetector CT in shoulder fractures

The aim of this study was to assess the multi-detector computed tomography (MDCT) findings in acute shoulder traumas compared to radiographic findings in patients referred to a level one trauma center. Two hundred and ten patients (128 male, 82 female, age 16-95 years, mean age 51.7 years) underwent shoulder MDCT due to acute trauma. Three main mechanisms of injury were established: falling (113 patients, 54%), traffic accidents (36 patients, 17%) and falling from a height (12 patients, 6%). Based on MDCT, a total of 311 fractures--152 in the scapula and 159 in the proximal humerus--occurred in 191 (91%) of the 210 patients. The two most common occult fractures were lesser tubercle and coracoid process fractures. In 20 (63%) of the patients with a comminuted fracture of proximal humerus the exact number of fracture fragments was underestimated in radiographs. MDCT with multiplanar reconstructions (MPR) is a recommended complementary examination in patients with complex proximal humerus fractures where the extent of the fractures and the position or origin of dislocated fragments is not clear on radiography. This may increase the accuracy of the fracture classification and reveal occult fractures in other parts of the shoulder.

Isolated fractures of the greater tuberosity of the proximal humerus

This review addresses isolated greater tuberosity fractures of the proximal humerus. The important aspects of the epidemiology, anatomy, fracture classification, associated injuries, and treatment are discussed. Although isolated greater tuberosity fractures are well recognized, there are few studies that specifically evaluate the outcome of these injuries. Our experience and review of the recent literature suggest that more precise evaluation of diagnostic criteria, treatment selection, and outcome is required.

Surgical anatomy of multipart fractures of the proximal humerus

The gross fracture anatomy was recorded in a cohort of 22 consecutive patients who underwent open surgery for 3-part and 4-part fractures of the proximal humerus and was compared with preoperative radiographs in a blind manner. It was noted that 8 of the 22 fractures did not correspond to any category of the Neer or AO/Orthopaedic Trauma Association/Jakob classification. These fractures had 3 displaced segments in terms of surgical anatomy, but the humeral head was free of soft tissue. In addition, the soft-tissue attachments to the head were closely related to the articular surface orientation on radiographs (medially oriented or not), rather than to the number of displaced segments or to the grouping of the AO/Orthopaedic Trauma Association/Jakob classification. Thus, in our study population, the current classification systems were inaccurate for realizing the fracture anatomy, particularly humeral head status. They would be accurate if the articular surface orientation was taken into account.

Fractures and tendon injuries of the athletic shoulder

Athletic injuries in the shoulder range from a routine strain or sprain to a potentially disabling fracture or tendon rupture. The level of sports participation plays an important role in diagnosis and treatment. The nonprofessional athlete may be more likely to sustain injuries secondary to under-training or improper technique. The professional athlete may be capable of play under much higher velocities and applied loads and, therefore, may be subject to higher energy trauma than the amateur athlete. In addition to standard treatment considerations, return to play time must also be decided. Decisions regarding definitive treatment may be modulated depending on an athlete's desire to return to his or her previous level of competition.

Variability of measurement of glenoid version on computed tomography scan

The purpose of the study was to determine the variability of measurement that might occur with rotation of the scapula in the coronal plane when computed tomography scanning is used. Ten dry scapula specimens had 4 sets of computed tomography scans performed at +20 degrees, +10 degrees, neutral, and -10 degrees of scapula rotation. The angle of glenoid version was then measured according to the technique of Friedman. The measured value for glenoid version was noted to vary by as much as 10 degrees on the same specimen with minor rotation of the scapula. This result occurred because of differences in the curvature of the vertebral border of the scapula. The measured angle of glenoid version was most likely to vary with rotation of the scapula 10 degrees downward (i.e., glenoid articular surface facing 10 degrees upward). For accurate and reproducible measurement of the glenoid version, it is essential that in the scout view the glenoid orientation is neutral (i.e., glenoid surface is perpendicular to the plane of the computed tomography cut).

Spiral CT and three-dimensional CT of musculoskeletal pathology. Emergency room applications

Spiral CT is a fast and effective modality for evaluating a wide variety of musculoskeletal abnormalities in the emergency department setting. The role of spiral CT in evaluating musculoskeletal trauma and musculoskeletal inflammation and infections is discussed, as is the use of multiplanar and three-dimensional imaging.

Reliability and reproducibility of radiographic interpretation of proximal humeral fracture pathoanatomy

Recent studies have demonstrated inconsistencies in the use of certain images for classifying proximal humerus fractures. Our purpose was to determine whether three-dimensional computed tomography or the level of expertise of the observers would improve the reliability and reproducibility of identifying specific anatomic fragments in proximal humerus fractures. Two groups of observers, nonexperts and experts in shoulder surgery, were asked to review the radiographs and three-dimensional computed tomography scans of 12 patients with proximal humerus fractures. Observers were asked to identify displaced fracture fragments, dislocation, and articular surface fractures. Both groups of observers displayed suboptimal reliability for the identification of displaced fracture fragments. The addition of three-dimensional computed tomography scans did not improve the reliability or reproducibility. Poor agreement for the purpose of classification seems to occur at the most fundamental level, the pathoanatomic description of the fracture. Inconsistencies may have been due to imprecise identification and measurement of individual fracture fragments, differing interpretations of the pathoanatomy, or both.

Surgical treatment of complex fracture of the proximal humerus

Sixteen patients aged 19 to 63 years (average, 52 years) were observed from 1.8 to 5.6 years (average, 3.8 years) after open reduction and internal fixation with or without external fixation of 3- and 4-part displaced fractures of the proximal humerus. There were 12, 3-part displaced greater tuberosity and surgical neck fractures with 6 concomitant dislocations. Four cases were 4-part fractures with 3 concomitant dislocations. Fixation was achieved with heavy sutures or wire that incorporated the rotator cuff tendon, tuberosities, and shaft combined with threaded pins or Hoffmann external fixation to enhanced stability for early rehabilitation. According to Neer's criteria, 14 (87%) of the 16 patients had satisfactory or excellent results. Two (13%) of the 16 had unsatisfactory results. The use of a technique of limited soft tissue dissection and internal fixation with or without external fixation achieved good fracture stability and a high percentage of satisfactory results. The limitations of the procedure include (1) patients who could not tolerate anesthesia, (2) complex displaced fractures in older patients with osteoporotic bone that cannot hold pins or external fixation, (3) older patients with 4-part fracture dislocations in which avascular necrosis of the humeral head occurs frequently and in which a subsequent endoprosthesis insertion is inappropriate if osteosynthesis fails, and (4) head splitting fractures. The described approach provides an alternative method for the treatment of complex displaced fractures of the proximal humerus.

Neer's classification system: a critical appraisal

The purpose of this study was to examine the interobserver agreement using Neer's classification system for fractures of the proximal humerus. A preliminary series of 28 fractures of the proximal humerus admitted to the hospital over a 5-year retrospective period was independently assessed by two radiologists and two orthopedic surgeons. The degree of agreement between paired observations was determined using a kappa statistic. The observations were assessed according to the number of fracture segments, as well as site of fracture segment. Most of the patients assessed were multisegment tuberosity fractures (n = 18). Results showed that the overall agreement between pairs of observers was 65% (average kappa = 0.45). It was also shown that, within the tuberosity group, the percentage agreement was 50%, with an average kappa = 0.35, indicating only fair interobserver agreement. Clinical implications of these findings are such that, as major surgical decisions are made dependent on Neer's classification, closer evaluation techniques--such as the computerized tomography scan and magnetic resonance imaging--should be used to classify the fracture segments accurately. This is particularly true with the fractured tuberosity subgroup.

Classification of proximal humerus fractures: The contribution of the scapular lateral and axillary radiographs

Trauma series radiographs of 50 proximal humerus fractures were used to assess the relative contribution of the scapular lateral and axillary radiographs to fracture classification with the Neer system. The radiographs were reviewed by an orthopaedic shoulder specialist, on orthopaedic traumatologist, a skeletal radiologist, and orthopaedic residents in their fifth and second years, respectively, of postgraduate training. In the first viewing radiographs were reviewed and classified in the following sequence: (1) after scapular anteroposterior view alone; (2) after review of scapular anteroposterior and lateral views; and (3) after review of scapular anteroposterior, lateral, and axillary views. A second viewing of the same 50 cases was performed 6 months later in a changed sequence: (1) after scapular anteroposterior view alone; (2) after review of scapular anteroposterior and axillary views; and (3) after review of scapular anteroposterior, axillary, and scapular lateral views. For the five observers, review of the scapular anteroposterior and axillary views achieved the final classification in 99% of cases. However, after review of the scapular anteroposterior and lateral views, the final classification was achieved in only 79% of cases (p < 0.05). These results indicate that when combined with the scapular anteroposterior radiograph, the axillary view contributes significantly more to fracture classification with the Neer system than the scapular lateral radiograph.

The Neer classification system for proximal humeral fractures. An assessment of interobserver reliability and intraobserver reproducibility

The radiographs of fifty fractures of the proximal part of the humerus were used to assess the interobserver reliability and intraobserver reproducibility of the Neer classification system. A trauma series consisting of scapular anteroposterior, scapular lateral, and axillary radiographs was available for each fracture. The radiographs were reviewed by an orthopaedic shoulder specialist, an orthopaedic traumatologist, a skeletal radiologist, and two orthopaedic residents, in their fifth and second years of postgraduate training. The radiographs were reviewed on two different occasions, six months apart. Interobserver reliability was assessed by comparison of the fracture classifications determined by the five observers. Intraobserver reproducibility was evaluated by comparison of the classifications determined by each observer on the first and second viewings. Kappa (kappa) reliability coefficients were used. All five observers agreed on the final classification for 32 and 30 per cent of the fractures on the first and second viewings, respectively. Paired comparisons between the five observers showed a mean reliability coefficient of 0.48 (range, 0.43 to 0.58) for the first viewing and 0.52 (range, 0.37 to 0.62) for the second viewing. The attending physicians obtained a slightly higher kappa value than the orthopaedic residents (0.52 compared with 0.48). Reproducibility ranged from 0.83 (the shoulder specialist) to 0.50 (the skeletal radiologist), with a mean of 0.66. Simplification of the Neer classification system, from sixteen categories to six more general categories based on fracture type, did not significantly improve either interobserver reliability or intraobserver reproducibility.

The reproducibility of classification of fractures of the proximal end of the humerus

The radiographs of ninety-five fractures of the proximal end of the humerus were classified with the Neer and the AO/ASIF systems by five orthopaedic surgeons who had a special interest in problems of the shoulder. Without access to their initial interpretations, the same five orthopaedic surgeons reevaluated the same radiographs eight weeks later. Intraobserver and intraobserver reliability were found to be fair or poor for both classification systems. Kappa values for the interobserver reliability were 0.40 for the Neer system and 0.53 for the AO/ASIF system. When the fractures were subclassified, according to the recommendations of the AO/ASIF, into groups and subgroups, reproducibility became progressively worse. Intraobserver reliability showed kappa values of 0.60 and 0.58, respectively. A so-called extended radiographic trauma series, consisting of three perpendicular radiographs, was available for thirty-five fractures; the third perpendicular projection did not significantly improve the reproducibility values for either classification compared with those obtained with only two perpendicular projections. We concluded that neither the Neer nor the AO/ASIF classification of fractures of the proximal end of the humerus is sufficiently reproducible to allow meaningful comparison of similarly classified fractures in different studies.